The present invention is related to wind energy plant with a rotor hub housing, which has a pitch bearing.
The pitch bearing is a rolling bearing with an inner and an outer ring, one of the rings being connected to the rotor hub housing and the other ring being connected to the rotor blade. Via a pitch system, which consists preferably of a pitch drive, a pitch control and for instance an auxiliary power supply, the rotor blade is rotated around its longitudinal axis and thus its angle of attack is adjusted towards the wind.
Known constructions for the rotor hub housing consist of a cast body with a flange for mounting the pitch bearing. Erich Hau describes in “Windkraftanlagen, Grundlagen, Technik, Einsatz, Wirtschaftlichkeit, 3th edition, Springer Verlag Berlin” in chapter 7.5, the entire contents of which is incorporated herein by reference, that the quality and the weight of the rotor blades is essentially determined by the construction of the blade joining to the rotor hub, besides to the proper execution of the rotor blade.
From DE 10 2004 023 773 B3, the entire contents of which is incorporated herein by reference, it is known to realise the pitch bearing with an inner ring, which is fixedly connected to the rotor hub. The outer ring connected to the rotor blade has an outer toothing which is in meshing engagement with a drive pinion of the pitch system for adjusting the rotor blade.
From DE 10 2004 017 323 A1, the entire contents of which is incorporated herein by reference, a blade joining for a rotor blade is known, in which an arresting device is provided, which keeps the rotor blade free from backlash with a predetermined angle position.
From WO 2004/090326 A1, the entire contents of which is incorporated herein by reference, a rotor hub body is known, which has a three-arm stiffening, formed in one piece, in the region of the rotor blade joining.
From DE 20 2004 003 521 U1, the entire contents of which is incorporated herein by reference, a rotor hub body for a wind energy plant is known, which is realised with ring flanges for fastening a pitch bearing. Inside the ring flanges, one stiffening bulkhead is provided at a time, which is realised either as a cast piece in one piece with the rotor hub housing, or which can be welded or screwed together with the rotor hub as an autonomous component part. The stiffening bulkhead is disposed in the rotor hub housing at a side facing the rotor shaft.
The present invention is based on the objective to provide a stiffening element for a rotor hub housing which simplifies the installation of the wind energy plant.